It is well known to extract energy from a flowing fluid by the use of suitable turbines which drive electrical generators to generate electricity. Such arrangements are commonly used in hydroelectric systems and usually use a head of water created through the construction of a dam to create a flow of water through conduits in which turbines are positioned. These systems whilst relatively efficient can negatively impact the environment during and following construction of the dams.
Other systems have been proposed and used which use the sea as a source of energy. Energy can be extracted from the sea by using the wave motion of the sea or tidal movement of the sea. A slow moving body of fluid however requires a large and costly prime mover to generate the necessary motion to drive energy extraction means. While the body of fluid may well be capable of providing substantial energy, it is the harnessing of that energy which is difficult. In order to generate an adequate supply of electricity to render a system profitable, a velocity of fluid flow should be high enough to avoid the necessity of providing costly and complicated prime movers. The costs of systems currently proposed or in use are too high to justify their broad implementation. In the various systems which are presently used, it is difficult to obtain a sufficiently high fluid velocity to enable efficient extraction of energy.